12666816 has 42 divisors (see below), whose sum is σ = 36308792. Its totient is φ = 4222080.

The previous prime is 12666809. The next prime is 12666821. The reversal of 12666816 is 61866621.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 10420 + ... + 11571.

Almost surely, 2^12666816 is an apocalyptic number.

12666816 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

12666816 is an abundant number, since it is smaller than the sum of its proper divisors (23641976).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

12666816 is a wasteful number, since it uses less digits than its factorization.

12666816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22009 (or 21996 counting only the distinct ones).

The product of its digits is 20736, while the sum is 36.

The square root of 12666816 is about 3559.0470634708. The cubic root of 12666816 is about 233.1072713028.

The spelling of 12666816 in words is "twelve million, six hundred sixty-six thousand, eight hundred sixteen".